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TopReview Of Literature
The forward movement based prediction considers zone prediction within a constrained forward movement of a target node (Lu, Fletcher, Ian, Pietro, & Zhang, 2008). It uses single reference node, limited random movement and does not consider sharp turns or obstacles which can be addressed by the optimal zone forming that considers any random movement. In addition, the received signal strength based prediction has better tracking accuracy over the triangulation method as long as multi-path fading is small and longer averaging availability (Malhotra, Krasniewski, Yang, Bagchi, & Chappell, 2005). The signal is spread in the lack of zone and errors are accumulated in the computation of both the distance and the angle and has limited non-random trajectory. This can be resolved by Zone finding and adaptive beam forming.
On the other hand, multi hop based prediction deploy the position locations of nodes estimation using multiple levels of reference nodes which increases the cumulative errors in multi hop measurements and has no beam adaptation used (Siuli et al. 2005). Thus, significantly reduces accuracy of tracking. This is over-come by zone forming with dynamic switching of reference nodes and dynamic ranging which provides improved accuracy in the location tracking. Furthermore, directional lines intersection based prediction localization of nodes use point of intersection of highly directional beams for low speed mobile anchor nodes (Zhang & Yu, 2010). This has higher overhead in scanning and does not address random trajectory. This can be addressed by zone forming and adaptive beam forming which reduces the scanning overhead in the random trajectory.